diff --git a/src/AtomUI.Controls/Calendar/Calendar.cs b/src/AtomUI.Controls/Calendar/Calendar.cs
index a514b0ea0..ab180a4b7 100644
--- a/src/AtomUI.Controls/Calendar/Calendar.cs
+++ b/src/AtomUI.Controls/Calendar/Calendar.cs
@@ -569,7 +569,7 @@ public class Calendar : TemplatedControl
       }
    }
 
-   internal DateTime DisplayDateInternal { get; private set; }
+   internal DateTime DisplayDateInternal { get; set; }
 
    #endregion
 
@@ -807,7 +807,7 @@ public class Calendar : TemplatedControl
       RemovedItems = new Collection<DateTime>();
    }
 
-   private void OnDisplayDateChanged(AvaloniaPropertyChangedEventArgs e)
+   protected virtual void OnDisplayDateChanged(AvaloniaPropertyChangedEventArgs e)
    {
       UpdateDisplayDate(this, (DateTime)e.NewValue!, (DateTime)e.OldValue!);
    }
@@ -833,7 +833,7 @@ public class Calendar : TemplatedControl
       c.OnDisplayDate(new CalendarDateChangedEventArgs(removedDate, addedDate));
    }
 
-   private void OnDisplayDate(CalendarDateChangedEventArgs e)
+   protected void OnDisplayDate(CalendarDateChangedEventArgs e)
    {
       DisplayDateChanged?.Invoke(this, e);
    }
@@ -1073,26 +1073,31 @@ public class Calendar : TemplatedControl
       }
    }
 
-   internal void UpdateMonths()
+   protected internal virtual void UpdateMonths()
    {
       CalendarItem? monthControl = MonthControl;
       if (monthControl != null) {
-         switch (DisplayMode) {
-            case CalendarMode.Month:
-            {
-               monthControl.UpdateMonthMode();
-               break;
-            }
-            case CalendarMode.Year:
-            {
-               monthControl.UpdateYearMode();
-               break;
-            }
-            case CalendarMode.Decade:
-            {
-               monthControl.UpdateDecadeMode();
-               break;
-            }
+         UpdateCalendarMonths(monthControl);
+      }
+   }
+
+   internal void UpdateCalendarMonths(CalendarItem calendarItem)
+   {
+      switch (DisplayMode) {
+         case CalendarMode.Month:
+         {
+            calendarItem.UpdateMonthMode();
+            break;
+         }
+         case CalendarMode.Year:
+         {
+            calendarItem.UpdateYearMode();
+            break;
+         }
+         case CalendarMode.Decade:
+         {
+            calendarItem.UpdateDecadeMode();
+            break;
          }
       }
    }
diff --git a/src/AtomUI.Controls/Calendar/CalendarItem.cs b/src/AtomUI.Controls/Calendar/CalendarItem.cs
index 64ff69959..e9a4c2958 100644
--- a/src/AtomUI.Controls/Calendar/CalendarItem.cs
+++ b/src/AtomUI.Controls/Calendar/CalendarItem.cs
@@ -25,7 +25,7 @@ namespace AtomUI.Controls;
 [PseudoClasses(CalendarDisabledPC)]
 internal class CalendarItem : TemplatedControl
 {
-   private const string CalendarDisabledPC = ":calendardisabled";
+   internal const string CalendarDisabledPC = ":calendardisabled";
    
    #region 公共属性定义
 
@@ -182,20 +182,20 @@ internal class CalendarItem : TemplatedControl
    /// <summary>
    /// The number of days per week.
    /// </summary>
-   private const int NumberOfDaysPerWeek = 7;
+   internal const int NumberOfDaysPerWeek = 7;
 
-   private HeadTextButton? _headerButton;
-   private IconButton? _nextButton;
-   private IconButton? _previousButton;
-   private IconButton? _nextMonthButton;
-   private IconButton? _previousMonthButton;
+   protected HeadTextButton? _headerButton;
+   protected IconButton? _nextButton;
+   protected IconButton? _previousButton;
+   protected IconButton? _nextMonthButton;
+   protected IconButton? _previousMonthButton;
 
-   private DateTime _currentMonth;
-   private bool _isMouseLeftButtonDown;
-   private bool _isMouseLeftButtonDownYearView;
-   private bool _isControlPressed;
+   protected DateTime _currentMonth;
+   protected bool _isMouseLeftButtonDown;
+   protected bool _isMouseLeftButtonDownYearView;
+   protected bool _isControlPressed;
 
-   private readonly System.Globalization.Calendar _calendar = new GregorianCalendar();
+   protected readonly System.Globalization.Calendar _calendar = new GregorianCalendar();
 
    internal Calendar? Owner { get; set; }
    internal CalendarDayButton? CurrentButton { get; set; }
@@ -328,7 +328,7 @@ internal class CalendarItem : TemplatedControl
       }
    }
 
-   private void SetDayTitles()
+   protected void SetDayTitles()
    {
       for (int childIndex = 0; childIndex < Calendar.ColumnsPerMonth; childIndex++) {
          var daytitle = MonthView!.Children[childIndex];
@@ -364,7 +364,7 @@ internal class CalendarItem : TemplatedControl
       }
    }
 
-   internal void UpdateMonthMode()
+   protected internal virtual void UpdateMonthMode()
    {
       if (Owner != null) {
          _currentMonth = Owner.DisplayDateInternal;
@@ -382,7 +382,7 @@ internal class CalendarItem : TemplatedControl
       }
    }
 
-   private void SetMonthModeHeaderButton()
+   protected virtual void SetMonthModeHeaderButton()
    {
       if (HeaderButton != null) {
          if (Owner != null) {
@@ -394,7 +394,7 @@ internal class CalendarItem : TemplatedControl
       }
    }
 
-   private void SetMonthModeNextButton(DateTime firstDayOfMonth)
+   protected void SetMonthModeNextButton(DateTime firstDayOfMonth)
    {
       if (Owner != null && NextButton != null) {
          // DisplayDate is equal to DateTime.MaxValue
@@ -409,7 +409,7 @@ internal class CalendarItem : TemplatedControl
       }
    }
 
-   private void SetMonthModePreviousButton(DateTime firstDayOfMonth)
+   protected void SetMonthModePreviousButton(DateTime firstDayOfMonth)
    {
       if (Owner != null && PreviousButton != null) {
          PreviousButton.IsEnabled = (DateTimeHelper.CompareDays(Owner.DisplayDateRangeStart, firstDayOfMonth) < 0);
@@ -441,10 +441,10 @@ internal class CalendarItem : TemplatedControl
 
             // SET IF THE DAY IS INACTIVE OR NOT: set if the day is a
             // trailing day or not
-            childButton.IsInactive = (DateTimeHelper.CompareYearMonth(dateToAdd, Owner.DisplayDateInternal) != 0);
-
+            childButton.IsInactive = CheckDayInactiveState(dateToAdd);
+            
             // SET IF THE DAY IS TODAY OR NOT
-            childButton.IsToday = (Owner.IsTodayHighlighted && dateToAdd == DateTime.Today);
+            childButton.IsToday = CheckDayIsTodayState(dateToAdd);
 
             // SET IF THE DAY IS SELECTED OR NOT
             childButton.IsSelected = false;
@@ -474,7 +474,25 @@ internal class CalendarItem : TemplatedControl
       }
    }
 
-   private void SetCalendarDayButtons(DateTime firstDayOfMonth)
+   protected virtual bool CheckDayInactiveState(DateTime dateToAdd)
+   {
+      if (Owner is not null) {
+         return DateTimeHelper.CompareYearMonth(dateToAdd, Owner.DisplayDateInternal) != 0;
+      }
+
+      return false;
+   }
+   
+   protected virtual bool CheckDayIsTodayState(DateTime dateToAdd)
+   {
+      if (Owner is not null) {
+         return Owner.IsTodayHighlighted && dateToAdd == DateTime.Today;
+      }
+
+      return false;
+   }
+
+   protected void SetCalendarDayButtons(DateTime firstDayOfMonth)
    {
       int lastMonthToDisplay = PreviousMonthDays(firstDayOfMonth);
       DateTime dateToAdd;
diff --git a/src/AtomUI.Controls/Calendar/RangeCalendar.cs b/src/AtomUI.Controls/Calendar/RangeCalendar.cs
index 88bc5e26d..8de3583b9 100644
--- a/src/AtomUI.Controls/Calendar/RangeCalendar.cs
+++ b/src/AtomUI.Controls/Calendar/RangeCalendar.cs
@@ -6,6 +6,13 @@ namespace AtomUI.Controls;
 
 public class RangeCalendar : Calendar
 {
+   public RangeCalendar()
+   {
+      SelectionMode = CalendarSelectionMode.SingleRange;
+   }
+   
+   internal DateTime SecondaryDisplayDateInternal { get; private set; }
+   
    internal CalendarItem? SecondaryMonthControl
    {
       get
@@ -17,7 +24,34 @@ public class RangeCalendar : Calendar
          return null;
       }
    }
+   
+   protected override void OnDisplayDateChanged(AvaloniaPropertyChangedEventArgs e)
+   {
+      UpdateDisplayDate(this, (DateTime)e.NewValue!, (DateTime)e.OldValue!);
+   }
+   
+   private static void UpdateDisplayDate(RangeCalendar c, DateTime addedDate, DateTime removedDate)
+   {
+      _ = c ?? throw new ArgumentNullException(nameof(c));
 
+      // If DisplayDate < DisplayDateStart, DisplayDate = DisplayDateStart
+      if (DateTime.Compare(addedDate, c.DisplayDateRangeStart) < 0) {
+         c.DisplayDate = c.DisplayDateRangeStart;
+         return;
+      }
+
+      // If DisplayDate > DisplayDateEnd, DisplayDate = DisplayDateEnd
+      if (DateTime.Compare(addedDate, c.DisplayDateRangeEnd) > 0) {
+         c.DisplayDate = c.DisplayDateRangeEnd;
+         return;
+      }
+
+      c.DisplayDateInternal = DateTimeHelper.DiscardDayTime(addedDate);
+      c.SecondaryDisplayDateInternal = DateTimeHelper.AddMonths(DateTimeHelper.DiscardDayTime(addedDate), 1) ?? c.DisplayDateInternal;
+      c.UpdateMonths();
+      c.OnDisplayDate(new CalendarDateChangedEventArgs(removedDate, addedDate));
+   }
+   
    protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
    {
       base.OnApplyTemplate(e);
@@ -56,4 +90,12 @@ public class RangeCalendar : Calendar
          }
       }
    }
+
+   protected internal override void UpdateMonths()
+   {
+      base.UpdateMonths();
+      if (SecondaryMonthControl is not null) {
+         UpdateCalendarMonths(SecondaryMonthControl);
+      }
+   }
 }
\ No newline at end of file
diff --git a/src/AtomUI.Controls/Calendar/RangeCalendarItem.cs b/src/AtomUI.Controls/Calendar/RangeCalendarItem.cs
index 26c7570b9..5ece4f658 100644
--- a/src/AtomUI.Controls/Calendar/RangeCalendarItem.cs
+++ b/src/AtomUI.Controls/Calendar/RangeCalendarItem.cs
@@ -1,5 +1,6 @@
 using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
 using Avalonia.Input;
 using Avalonia.Interactivity;
 
@@ -54,6 +55,12 @@ internal class RangeCalendarItem : CalendarItem
       }
    }
 
+   protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
+   {
+      base.OnApplyTemplate(e);
+      SetupNextButtonVisible();
+   }
+
    private void SetupNextButtonVisible()
    {
       IsNextButtonVisible = !IsPrimary || Owner?.DisplayMode == CalendarMode.Decade ||
@@ -77,4 +84,45 @@ internal class RangeCalendarItem : CalendarItem
       base.HandleMonthCalendarButtonMouseUp(sender, e);
       SetupNextButtonVisible();
    }
+   
+   protected internal override void UpdateMonthMode()
+   {
+      if (Owner is RangeCalendar owner) {
+         _currentMonth = IsPrimary ? owner.DisplayDateInternal : owner.SecondaryDisplayDateInternal;
+      } else {
+         _currentMonth = DateTime.Today;
+      }
+   
+      SetMonthModeHeaderButton();
+      SetMonthModePreviousButton(_currentMonth);
+      SetMonthModeNextButton(_currentMonth);
+   
+      if (MonthView != null) {
+         SetDayTitles();
+         SetCalendarDayButtons(_currentMonth);
+      }
+   }
+   
+   protected override void SetMonthModeHeaderButton()
+   {
+      if (HeaderButton != null) {
+         if (Owner is RangeCalendar owner) {
+            var targetDate = _isPrimary ? owner.DisplayDateInternal : owner.SecondaryDisplayDateInternal;
+            HeaderButton.Content = targetDate.ToString("Y", DateTimeHelper.GetCurrentDateFormat());
+            HeaderButton.IsEnabled = true;
+         } else {
+            HeaderButton.Content = DateTime.Today.ToString("Y", DateTimeHelper.GetCurrentDateFormat());
+         }
+      }
+   }
+   
+   protected override bool CheckDayInactiveState(DateTime dateToAdd)
+   {
+      if (Owner is RangeCalendar owner) {
+         var targetDate = _isPrimary ? owner.DisplayDateInternal : owner.SecondaryDisplayDateInternal;
+         return DateTimeHelper.CompareYearMonth(dateToAdd, targetDate) != 0;
+      }
+   
+      return false;
+   }
 }
\ No newline at end of file